Anacharis just does that... they tend to shoot out roots from anywhere along
the stem. If you want to use this as a guide to use for cuttings go ahead.
Unlike my cabomba which seems to grow mishapen new growth from the place
where I've cut it when pruning, anacharis doesn't even let this slow it
down. I one took a foot long section and cut it into one inch lengths and
planted all of these and now I have a tank full of anacharis. It's a good
oxgenator and it's kinda pretty waving around in the filter current.